Due to the standards such as IEEE519 and IEC 1000-3-2 imposing a limit on harmonic current drawn by equipment, it is necessary to develop a power system whose AC line is low in harmonics and power factor is close to unity. To cope with these limitations, many power factor correction (PFC) converters employ a boost topology at their input stage. But it is bulky, costly and the Secondary Switch voltage stress is heavy, which is the general characteristic of step-up topology. So it is not desirable to use in low power level applications (like a Notebook PC Adapter). Therefore, simple PFC converters with a built-in Notebook PC should be developed.
Based on two stage approach, Primary stage for AC/DC PFC is buckboost topology operating in discontinuous conduction mode (DCM) and Secondary stage for DC/DC regulation converter is flyback topology operating in continuous conduction mode (CCM). To make a small size adapter for notebook, it`s the most important that link capacitor make a small size. So the buckboost AC/DC PFC converter is more suitable than Boost AC/DC PFC converter because buckboost converter makes lower link voltage than Boost converter. It makes a small link`s capacitor and small voltage stress of secondary switch.
DC/DC flyback converter must has snubber circuits to make switch’s voltage stress low. Non-dissipative snubber(energy regenerative snubber) applied to flyback is analyzed.
The propose converter gives the good power factor correction, low line current harmonic distortions, low link voltage (low device voltage stress), tight output voltage regulations and small size. The validity of the analysis and the design is verified by a simulation and an experiment
